Wendee Holtcamp wrote:
>I am teaching intro college biology and am about to mention the peppered
>moth classic example of natural selection. I know there has recently been
>some criticism of the study by creation scientists, but was unable to locate
>any specifics from a web search. Does anyone know what criticism has been
>offered about this study, and why?
The peppered moth example says something about selection, but little about
evolution by mutation. Say you had an island population of 2000 goats that
were evenly split between blue-eyed and brown-eyed animals. In order to
reduce the population, it is decided to eliminate half the goats, and
arbitrarily it is decided to exterminate the blue-eyed animals by shooting
them. Some years later the population is, say, 20% blue-eyed and 80%
brown-eyed. One could erroneously conclude that the goats were having
fewer blue-eyed offspring to avoid being shot. But we should know that the
gene pool has been altered by simply reducing those capable of producing
blue-eyed offspring.
A better argument for evolution by mutation could be made by citing those
moths that have developed "radar jamming" to avoid being eaten by bats. It
would be hard to argue that some moths have always been born into the world
with sound emitting capabilities which, luck-would-have-it, are pitched at
bat frequencies. Evolution by mutation is a more logical argument in this
case.
I live close to Luray Caverns in Virginia. When the caverns were
discovered, they found sightless fish and crickets living there. The fish
had tiny indentations where eyes once were, but after millions of years of
breeding, were shed as unnecessary where there is no light. Once the
selective pressure of sunlight and predators was removed the fish
genetically discarded what was unneeded.
Dick Fischer - The Origins Solution - www.orisol.com
"The answer we should have known about 150 years ago."
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